red chinese-style jacket with yellow piping (no collar, vent slits on hips, just below waist length, open in front held at neck with a gold pin), with knee-length dress (long-sleeved, probably also red, with a thin belt at waist), black stiletto heels

12:09 - there's a thread stuck to the centre top of the camera lens in Oyuka's CU. It returns at 12:22 when Oyuka goes for Mrs Peel knee, and again as Mrs Peel bows to Sensei at 12:39.

5:00 - The sign behind the security guard reads "Industrial Developments", but whenever the company is mentioned by characters, it's a somewhat obvious overdub of Industrial Deployments - must have been a legal issue, similar to the redubs in A Sense of History.

14:39 - "This heralds a new age Mr Steed; computers no bigger than a cigarette box." Prophetic words indeed! Was Armstrong really planning on building an Android 'phone? (ha ha)

15:08 - the cultural confusion: Steed asks if Tusamo has just quoted Confuscius but Hirachi is clearly meant to be a Japanese company, not Chinese. Emma makes the same mistake at 16:38.

But Benson had gone in before Steed and it was clearly Jephcott arriving after him!

18:10 - Mrs Peel's cover when investigating Jephcott is that she represents a firm called "Winnell and Fentle's chain stores", a Spoonerist reference to series produces (Julian) Wintle and (Albert) Fennell.

26:29 - the cameraman is slow to get focus on the change of shot back to Armstrong.

27:27/28:20 - Surely Steed can hear Dr Armstrong's side of his conversation with Benson - I'd prick up my ears if Armstrong said "But Lambert's dead".

28:47 - weird smudge appears at top left - it looks like someone has scribbled on the film.

37:45/38:14 - Steed turns the thermostat up from 40°F to 82°F, but even that's not really hot enough to make them break out in a sweat unless their jackets are particularly warm.

39:52 - Steed appears to dial 246 as the start of Emma's number.

41:51 - Steed uses the phrase "government by automation" which I'm sure is repeated in the 1967 android thriller, Never, Never Say Die.

44:53 - That looks like Ray Austin flying over the desk.

46:45 - It has long been held that when the cybernauts are fighting in Armstrong's warehouse, knocking boxes about the place, you can just catch a stage hand's hand pushing one of them over on the left of the screen. Hacving rewatched the restored footage, it's clear that it's Roger's right hand, and not a badly-positioned stagehand at all.

50:00 - Steed's vintage car in the tag scene, the Beeston Humber 16/20hp, appeared in Those Magnificent Men in Their Flying Machines (1965) as the car belonging to the German entrant, Colonel Manfred von Holstein (Gert Fröbe). It's from the film that I have been able to confirm the colour and number plate as when the car was recently auctioned the plate was no longer in place. The car is painted post office red with brass metalwork and burgundy leather upholstery.

This and the next episode sit strangely together, as they both have a wheelchair-bound diabolical masterminds, although their motives are diametrically opposed.

running time: 49'56"

A note on the timecodes
Where I have listed two sets of timecodes, the first is from the 2009-11 Optimum Releasing/Studio Canal DVD sets, any other timecodes are from the A&E and Contender DVD sets from a decade beforehand.
The new releases have been remastered and their frame rate has been changed, resulting in a shorter running time. However, the picture quality has increased markedly. I assume this is because they used a simple 2:2 pulldown (24 @ 25) when converting from the original film masters (film runs at 24 frames per second, while PAL runs at 25fps, the new DVDs are in PAL format).
This pulldown was also the cause of audio errors on many episodes, especially for Series 5, as the audio sped up to match the new rate (4% faster), rather than being properly pitch-shifted. Checking the dialogue sheets, which list the feet and frames of the reels, it looks like the speed change is around 5.04%, so there may be some cuts as well - probably from around the commercial breaks and ends of reels, as they amount to about 25 seconds. All my assumptions are based on the episodes having been filmed on standard 35mm film, which has 16 frames per foot and runs at 24 frames per second, so a minute of footage uses 90 feet of film (1,440 frames).
These audio errors have been corrected in the currently available DVDs, but the 2:2 pulldown remains. There is also the addition of a Studio Canal lead-in, converted to black and white to match the episode for Series Four, but colour for Series Five, adding an extra 18 or 19 seconds to the runnning time and making it harder to match timecodes with previous releases. It's annoying that it has been slapped on every single episode, Series 1-3 didn't suffer this indignity.
The previous Contender and A&E DVD releases didn't seem to suffer from these problems, so I assume they either used soft telecine and preserved the original 24fps rate of the film (my preferred option in DVDs) or they used 24 @ 25 pulldown (2:2:2:2:2:2:2:2:2:2:2:3 Euro pull-down). Let's hope the much-rumoured bluray release will revert to native 24fps with soft telecine so we won't have these problems again.